This invention relates to ceramic compositions containing a distillable binder, shaped articles formed therefrom and preparative processes for the shaped articles and for the compositions.
Shapeable ceramic or preceramic compositions containing polymeric binders wherein the polymer provides a matrix for the composition are well known. Examples of such polymeric binders are epoxy resins, phenolic resins, polyimides, polysulfones, polystyrenes, polyaramids, polyesters and polycarbonates; see, for example, Lee et al., "Metal and Polymer Matrix Composites", Noyes Data Corp., 1987, pages 10 to 18 and 121 to 123. Polymers provide plastic properties which impart toughness and shapeability to ceramic components. However, the polymers must be destructively burned off during densification/firing of the ceramic composite. Frequently, undesirable carbonization occurs during removal of the polymer binder by the technique of burning it off.
So far as can be determined, the art until this time has been unaware of a process for forming ceramic articles from a ceramic/binder composition without the necessity for destructive removal of the binder with the dangers attendant thereon of contaminating the ceramic with undesired polymer residues. It is the subject of this invention to provide compositions of ceramic particulates and methods for making and working the compositions so that it will now be possible to make ceramic articles without the necessity and cost of destroying the polymeric binder matrix used to hold the ceramic particles together until the sintering step.